Identification of novel nitroreductases from Bacillus cereus and their interaction with the CB1954 prodrug

Gwenin, V.V. and Poornima, P. and Halliwell, J. and Ball, P. and Robinson, G. and Gwenin, C.D. (2015) Identification of novel nitroreductases from Bacillus cereus and their interaction with the CB1954 prodrug. Biochemical Pharmacology, 98 (3). pp. 392-402. DOI: 10.1016/j.bcp.2015.09.013

33715.pdf - Accepted Version
Available under License Creative Commons Attribution Non-commercial No Derivatives.

Download (4MB) | Preview


Directed enzyme prodrug therapy is a form of cancer chemotherapy in which bacterial prodrug-activating enzymes, or their encoding genes, are directed to the tumour before administration of a prodrug. The prodrug can then be activated into a toxic drug at the tumour site, reducing off-target effects. The bacterial nitroreductases are a class of enzymes used in this therapeutic approach and although very promising, the low turnover rate of prodrug by the most studied nitroreductase enzyme, NfnB from Escherichia coli (NfnB_Ec), is a major limit to this technology. There is a continual search for enzymes with greater efficiency, and as part of the search for more efficient bacterial nitroreductase enzymes, two novel enzymes from Bacillus cereus (strain ATCC 14579) have been identified and shown to reduce the CB1954 (5-(aziridin-1-yl)-2,4-dinitrobenzamide) prodrug to its respective 2�-and 4�-hydroxylamine products. Both enzymes shared features characteristic of the nitro-FMN-reductase superfamily including non-covalently associated FMN, requirement for the NAD(P)H cofactor, homodimeric, could be inhibited by Dicoumarol (3,3�-methylenebis(4-hydroxy-2H-chromen-2-one)), and displayed ping pong bi bi kinetics. Based on the biochemical characteristics and nucleotide alignment with other nitroreductase enzymes, one enzyme was named YdgI_Bc and the other YfkO_Bc. Both B. cereus enzymes had greater turnover for the CB1954 prodrug compared with NfnB_Ec, and in the presence of added NADPH cofactor, YfkO_Bc had superior cell killing ability, and produced mainly the 4�-hydroxylamine product at low prodrug concentration. The YfkO_Bc was identified as a promising candidate for future enzyme prodrug therapy.

Item Type: Article
Subjects: Research Publications
Departments: College of Physical and Applied Sciences > School of Chemistry
Date Deposited: 17 Oct 2015 02:39
Last Modified: 28 Sep 2016 02:33
ISSN: 0006-2952
URI: http://e.bangor.ac.uk/id/eprint/5657
Identification Number: DOI: 10.1016/j.bcp.2015.09.013
Publisher: Elsevier
Administer Item Administer Item

eBangor is powered by EPrints 3 which is developed by the School of Electronics and Computer Science at the University of Southampton. More information and software credits.